Such a system is known per se. Such a system is often placed in stores, such as department stores, where customers themselves can take the merchandise to be purchased from the position where it is displayed to a checkout to pay for it. In such stores, it is possible to reach the exit of the store without visiting a checkout to check out the merchandise. It is therefore fairly easy to steal, since, when leaving the store, the merchandise can be inconspicuously taken along, for instance hidden in a bag, without being paid for. To be able to discover theft of merchandise, a number of articles are provided with antitheft labels. The antitheft labels are so designed that when passing a passage, in this case the exit, a transceiver device set up there can detect the antitheft label. When the transceiver device detects an antitheft label, an alarm goes off. The alarm can be a visible alarm, such as, for instance, a flashing or rotating light attracting attention, or an audible alarm, such as, for instance, a siren. A security officer is alerted by the alarm and will try to find the antitheft label that has been detected by the theft security system and proceed to stop a customer to prevent theft. When a customer checks out an article that is fitted with an antitheft label, the antitheft label, after payment, will be either removed from the article by the employee at the checkout, or be deactivated. The transceiver device can no longer detect the antitheft label then. The customer can leave the store without an alarm going off.
A disadvantage of such a system is that when employees at the checkout forget to remove the antitheft label from the article which has been paid for, or forget to deactivate the antitheft label of the article paid for, the alarm will go off, which will be embarrassing at the least to the customer. A security officer will then hasten to the customer to stop the customer. If this situation occurs frequently, this may eventually lead to loss of customers. Also, in such a situation, the customer is unnecessarily detained and it further means that the security officer cannot at that moment respond, for instance, to alarms going off elsewhere.